Exhibit 4.1

 



PROOF PROOF   PROOF PROOF PROOF PROOF PROOF N U M B E R SEE REVERSE FOR CERTAIN DEFINITIONS   INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE C o M M o n s T o C K   This CerTifies ThaT: PROOF is The owner of FULLY PAID AND NON-ASSESSABLE   SHARES OF COMMON STOCK OF $0.0001 PAR VALUE EACH OF Aridis PhArmAceuticAls,   inc. transferable on the books of the Corporation in person or by duly   authorized attorney upon surrender of this certificate duly endorsed or   assigned. This certificate and the shares represented hereby are subject to   the laws of the State of Delaware, and to the Certificate of Incorporation   and Bylaws of the Corporation, as now or hereafter amended. This certificate   is not valid until countersigned by the Transfer Agent. WITNESS the facsimile   seal of the Corporation and the facsimile signatures of its duly authorized   officers. COUNTERSIGNED: DATED: PHILADELPHIA STOCK TRANSFER, INC. 2320   HAVERFORD RD., SUITE 230, ARDMORE, PA 19003 TRANSFER AGENT BY: AUTHORIZED   SIGNATURE CHAIRMAN CHIEF EXECUTIVE OFFICER PROOF PROOF PROOF PROOF PROOF   PROOF PROOF CUSIP040334104 SHARES A 


    




 










The following   abbreviations, when used in the inscription on the face of this certificate,   shall be construed as though they were written out in full according to applicable   laws or regulations: TEN COM - as tenants in common TEN ENT - as tenants by   the entireties UNIF GIFT MIN ACT -   ....................Custodian.................... (Cust) (Minor) JT TEN - as   joint tenants with right of survivorship and not as tenants in common under   Uniform Gifts to Minors Act   ................................................... (State) Additional   abbreviations may also be used though not in the above list. For Value   Received, hereby sell, assign and transfer unto PLEASE INSERT SOCIAL SECURITY   OR OTHER IDENTIFYING NUMBER OF ASSIGNEE (PLEASE PRINT OR TYPE NAME AND   ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE) Shares of the stock represented by   the within Certificate, and do hereby irrevocably constitute and appoint   Attorney to transfer the said stock on the books of the within named   Corporation with full power of substitution in the premises. Dated NOTICE:   THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN   UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION OR   ENLARGEMENT OR ANY CHANGE WHATSOEVER. Signature(s) Guaranteed By The   Signature(s) must be guaranteed by an eligible guarantor institution (Banks,   Stockbrokers, Savings and Loan Associations and Credit Unions with membership   in an approved Signature Guarantee Medallion Program), pursuant to SEC Rule   17Ad-15. THE CORPORATION WILL FURNISH TO ANY STOCKHOLDER, UPON REQUEST AND   WITHOUT CHARGE, A FULL STATEMENT OF THE DESIGNATIONS, RELATIVE RIGHTS,   PREFERENCES AND LIMITATIONS OF THE SHARES OF EACH CLASS AND SERIES AUTHORIZED   TO BE ISSUED, SO FAR AS THE SAME HAVE BEEN DETERMINED, AND OF THE AUTHORITY,   IF ANY, OF THE BOARD TO DIVIDE THE SHARES INTO CLASSES OR SERIES AND TO   DETERMINE AND CHANGE THE RELATIVE RIGHTS, PREFERENCES AND LIMITATIONS OF ANY   CLASS OR SERIES. SUCH REQUEST MAY BE MADE TO THE SECRETARY OF THE CORPORATION   OR TO THE TRANSFER AGENT NAMED ON THIS CERTIFICATE. COLUMBIA PRINTING   SERVICES, LLC - www.stockinformation.com